The proposed research will use archival data to test statistical models of the growth and spread of drug markets and related problems across California over 17 years (1990-2006). We will examine the broad frame of market and enforcement activities related to illegal drugs, but emphasize studies of the methamphetamine market (a market that has spread across California during this time). This research will assess the degree to which community and neighborhood risk factors (e.g., impoverishment) accelerate the growth of drug markets and related problems (e.g., overdoses, violence). Bayesian space-time disease models will be applied at different levels of geographic resolution (e.g., cities and zip code areas). The project will answer three specific research questions: 1) Is there evidence for the spatial diffusion of drug market activities over time? 2) Is the rate of growth of drug markets a function of local population "frailties?" 3) What are the spatial and temporal relationships between local indicators of drug market activities and social problems often associated with drug markets? In order to answer these questions, the project will couple data from an in-house proprietary database, the California Index Locations Database (CILD), to data that indicates drug markets, enforcement activities and related problems. Accompanying the three specific research questions are three methodological steps: 1) Define and apply hierarchical generalized linear models with spatial correlation. 2) Define and apply variable coefficient models for drug epidemiology. 3) Define and apply methods for the spatial analysis of location distributions on a network. The short-term goal of this work is to provide the data and methods necessary to assess the development of drug market activities across broadly different ecological settings over time. The long-term goal is to establish the societal conditions that affect the dynamic evolution of drug markets across communities within states in the US. Greater understanding of the broader sociodemographic conditions that enable the development of drug markets will enable the formulation of effective state-wide drug prevention strategies.